Connect a model — Eva docs

One API key in the environment connects Anthropic or OpenAI, and your key never reaches a settings file, a log, or the session record.

Eva talks to Anthropic and OpenAI, so a key is the whole setup.

export ANTHROPIC_API_KEY=sk-ant-...
eva

That is it. There is no login step, no config file to edit, and no account. For OpenAI models, export OPENAI_API_KEY instead and pick one:

export OPENAI_API_KEY=sk-...
eva --model openai/gpt-5.4

A local model behind Ollama, or any OpenAI-compatible endpoint, is one config entry away — providers shows it.

Where your key goes, and where it does not

Your key never reaches a settings file, a log, or the session record. Eva reads it from the environment at the moment it opens a request and holds it nowhere else.

This matters because a session record is a file on your disk that you may share, copy into an issue, or hand to another tool. It never contains a credential.

Choose a different model

Set it for one run with a flag:

eva --model anthropic/claude-sonnet-5

Or set it inside a session with a command:

/model anthropic/claude-sonnet-5

/model with no argument shows the current model and offers the ones Eva knows about. See models.

What Eva costs

Eva reports what a provider says a request cost, and marks an estimate as an estimate. Cost and usage explains the difference, and why Eva refuses to guess.

Next: your first run.